Factors affecting successful closure of hemodynamically significant patent ductus arteriosus with indomethacin in extremely low birth weight infants.

BACKGROUND: The incidence of patent ductus arteriosus (PDA) is high in extremely low birth weight (ELBW) infants. Indomethacin has been widely used in the prophylaxis and treatment of hemodynamically significant PDA. This retrospective study was undertaken to identify factors such as birth weight, gestational age, gender, fetal growth retardation, ductal size, timing of the first dose of indomethacin and side effects of indomethacin, which may affect the successful closure of the PDA with indomethacin in ELBW infants.

METHODS: A cohort of 139 ELBW infants who had received indomethacin treatment for PDA during a consecutive period of more than three years (September 2000 to December 2003) was retrospectively analyzed. Administration

RESULTS: of indomethacin was associated with closure of PDA in 108 (77.7%) of 139 ELBW infants, and only 19.4% of infants required surgical ligation of the ductus eventually. There was no significant relationship between closure of PDA with gestational age, gender, fetal growth retardation, and ductal size. A higher birth weight and early use of indomethacin after birth could significantly increase the closure rate of PDA (P<0.05). Side effects of indomethacin such as transient oliguria and hyponatremia during indomethacin therapy did not affect PDA closure.

CONCLUSIONS: Indomethacin is effective for the treatment of PDA in ELBW infants. A higher rate of ductal closure is related to the increase of birth weight. PDA closure with indomethacin is age-related, and early administration of indomethacin could increase PDA closure and reduce the incidence of hyponatremia. There is no significant difference in major morbidities such as bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP) after early treatment. Early screening for hemodynamically significant PDA in ELBW infants and early treatment with indomethacin are recommended.